Molten metal seal for annealing furnaces



F. LEPKA MOLTEN METAL SEAL FOR ANNEALING FURNACES May 28, 1946.

Filed Nov. 2, 1942 2 Sheets-Sheet 1 I ll::-

' I INVENTOR F/%ED L'EPKA,

Mayz& 1946.\ F LEPKA 2,401,l70

` MOLTEN METAL sEAI FOR-ANNEALING FURNACES Fied Nov. 2, 1942 2 Sheets- Sheet 2 INVENTOR FkED LEPKA,

z %a O omey. I

Patente'd May 28,

MOLTEN METAL SEAL FUBNACES ron mmm&

me Lepka, Breekville, Ohio, asalnor to ne American Steel and wlreconay oi' Ne' Jersey', a c-poration o! New Jersey Ap ctomNove bem, 1942, se- No. (84,234 V emm. (c. ass-) i r This invention relates to molten metal seals and more particularly to such a seal that isused tor retaining atmosphere under annealing covers.

Commonly sand or oil seals are used, but the sand seals are objectionable because. 'oi' leakage of gas through the seal and also because of the fine dust particles which cause scratching of bright surfaces. The oil seal is gas tight but requiresspecial flange construction on the inner cover to eflect a seal at a point where the oil will remain sumciently cool to 'prevent ignition thereof. The oil has also been kept below the ignition temperature by the use of cooling water, -but this scheme results in loss oi' heat. There is also the dangerof serious buns to operators from burning oil which is sprayed about by protective atmosphere explosions. Another disadvantage is the dripping of theoil from the Inner annealing covers. i t

An object of this lnvention is to provide a gas tight seal which will not ignite during annealing. Another object is to provide a metallic seal in In operation the inner cover is placed over the steel charge 3 and its open end extends into the molten metal seal I, thus preventingleakage of air into the steel and also preventing the escape f of any special atmosphere !rom the cover. The .metal of the seal is kept in a molten state by means oi' the electrical heating elements until a the inner cover is removed.

which the metal is retained in a -molten state 4 untfl the cover is removed.

The foregolng and other objects will be more apparent after rei'erring to the following specification and attached drawings in which Figura 1 is a sectional view of one embodiment oi' the invention;

Figura 2 is a' section on the line lI--II oi' Figurega.

Figura 3 is a fragmental view similar to Figure 1, but showing a vention: and

Figure 4 is sectional view second embodiment of the intaken on the line IV-IV of mure 3.

Reterring more particularly to Flgures 1 and 2of the drawings, reference numeral l indicates a heating furnace of .any'conventional design.

within the i'urnace is a base 2 upon which a charge or steel 3 is placed. An inner cover I with straight vertical sides protects the steel and r extends down into the molten metal se'al s.- The sealingmetal maybe any metal having a low melting point such as lead, solder, or 'Rose a metal. The seal may be shallower than the usual sand or oil seal, and is conflned in a metal channel i which is supported by spaced rings 'l and a, connected by a plate 9. In the opening between channel 0 and plate 9 are the electrical heating elements III which may be applied' in multiple in order to give flexibility oi' operation. These heating means may be thermostatically 'controlled to cut oil" at predetermined temperatures. The seal metal is not heated to a point of volatlization.

Figures 3 and 4 illustrate a second embodiment of the invention. The metal channel 6' tor the sealis formed by two spaced rings 1 4' connected by means oi the plate 0'. As best shown in Figure 4, a plurality of gas bumers !2 are-located around the periphery of the outer ring, and the flames are directed into v the combustion chamber 43. It will be understood that other tuels, such as oil, may be subi stituted for the gas. These burners may be thermostatically controlled to cut oi! at predete`r-' mined temperatures !or Operations. a

While two embodiments of the invention have been described, it will be apparent to one skilled in theart that other modiflcaticns and adaptations may be made while remaining within the scope of the following claims.

economy and control of v l: A metallic seal of the class described comprsing a base for receiving a charge to be heated, a channel surrounding said base, a low melting point sealing metal therein, an open ended cover adapted to be placed over the charge with its open end' extending into the sealing metal and means located in the base forkeeping the sealing metal molten as long as the cover remains therein.

2. A metallic seal of the class described comprising a base for receiving a charge to' be heated. a channel surrounding said base for receiving a 'scaling metal, and means located in the base for heating the scaling metal.

3. A metallic seal ot the class described comprising a base tor receiving a charge to be heated,

a channel surrounding saidbase for receiving a sealing metal, the level of said sealing metal bein below the top of said base, and means located in the base for keeping the scaling metal molten.

4. A metallic seal of the class described comprising abase for receiving a charge to be heated,

a channelsurrounding said base for receiving-a sealing metal. and electrical means located in the base for heating the sealing metal. i

5. A metallic seal of the class described comprising a base 'for receiving a charge to be heated.

It is understand that the metal is well insulated 'in order to prevent loss of heat.

a channel surrounding said base !or receiving a sealing metal,`and a flame located in the base forheating the sealing metal.

FRED LEPKA. 

